Milking Management Blog

Stray Voltage Testing

Low voltages can have an adversarial effect on cell counts and some studies have shown that just 0.75 of a volt could increase cell counts. Just 2 volts can stop cows entering the milking point and also make them very edgy. The stray voltage test can detect these very small changes and provide resolutions in alleviating the effect of stray voltage. Dairy industry standard requires the milliamps not to exceed 1 and AC voltage not to exceed 0.5 volt .


Cutting Corners on a Milking Machine Test Does Not Pay

Recent visits to three new customers were very concerning, each farm had recently had a Static milking machine test and all requirements of the test report passed.
Each Farm had issues with Cell Counts Bactoscan and excessive Mastitis incidence (50%)
All farms had poor effective reserves
High vacuum levels to compensate for the low effective reserve.
Vacuum recovery tests were not compliant
The jar system took well over six seconds to stabilise
The Vacuum controller was sited incorrectly with the sensing tube pointing in the wrong direction.
These are just some of the faults found. on one farm they had spent over twenty five thousand pounds on a cluster flush and the clusterflush was fitted on a badly tested machine.
Milking machines are used 5-6 or more hours every day. Broken-down machines or machines operating inefficiently cost in reduced milk, time, damaged udders, and reduced milk quality. Regular milking machine testing will allow performance at high efficiency.
It really doesn’t pay to have a poor inadequate milking machine test. Check out this link

Regulator Airline

Differences in vacuum levels between the receiver and regulator should not exceed 0.6kpa. The most common cause of ineffective vacuum regulation is an excessive vacuum difference between the receiver and regulator because of either improper regulator location or excessive restrictions in pipelines and fittings between these two components. Regulators mounted on branch lines often perform inefficiently unless the connecting lines are adequately sized to minimize frictional losses. Branch lines are fine as long as they are sized

Regulators mounted on or near the distribution tank often tend to oscillate because of the cyclic vacuum changes in pulsator airlines. Preferably, the regulator (or its sensor) should be connected near the sanitary trap so that it can sense, and quickly respond to, vacuum changes caused by "unplanned" air admission entering the system through the teatcups

Milkline vacuum stability in milking machine installations.

The direct connection between the transient vacuum drop and its cause could be established for most drops during milking observations. A high frequency of transient vacuum drops in the milkline was associated with a high level of mastitis and a high new infection rate as inferred from changes in somatic cell counts for individual cows. The frequency of vacuum drops during one milking is only a rough indication of the long-term vacuum stability

During milking the teat cup liner is the interface between the teat of a dairy cow and the milking system

Milking performance of milking machines that matches the production capability of dairy cows is important in reducing the risk of mastitis, particularly in high-producing cows.

Examination of the milking performance of the milking system with a milking-time test allows an evaluation of the performance that can cope with high producing cows, indicating the possibility of reducing the risk of mastitis caused by inappropriate claw vacuum.


The Milking System

Bovine mastitis is typically caused by microbial infection of the udder, but the factors responsible for this condition are varied. One potential cause is the milking system,
Milking performance of milking machines that matches the production capability of dairy cows is important in reducing the risk of mastitis, particularly in high-producing cows.
The factors affecting mean claw vacuum are claw type, milk-meter and vacuum shut-off device
Correctly installed equipment reduces the risk of mastitis caused by inappropriate claw vacuum.
Thus, proper maintenance and operation of any milking system is a key aspect of successful milking.


Somatic cell count targets

Controlling cell counts in the dairy herd by following endorsed practices would be simple, but unfortunately due to the intrinsic variability of conditions on dairy farms in the UK and the nature of mastitis incidence, the problem of high Somatic Cell Counts can be particularly mystifying for many herds that meet best practice recommendations but fail to significantly lower cell counts.
SCC target for all dairy herds may be suitable or in many cases achievable. However, due to an increasing awareness of cow welfare and pressure to improve milk quality, it is obvious that most dairy farmers have to attempt to improve levels of both clinical and subclinical mastitis in their herds, and to benefit from the advantages they can receive for producing milk with lower SCCs.
The generally-quoted aims for mastitis control and milk quality on UK dairy farms are:
A mastitis incidence rate of no more than 30 cases per 100 cows per year.
A mastitis persistence rate of no more than 20% of the herd affected per year.
A mastitis re-occurrence rate of less than 10% of the total number of cases.
A herd-average Somatic Cell Count below 150,000 cells/ml.
An average Bactoscan result of below 5,000.
In general terms, rule of thumb is for every 100,000 cells/ml increase in the herd bulk SCC, there is an 8-10% increase in the proportion of cows infected in the herd. Persistently high individual cow SCC results can indicate chronic mastitis problems.


Choosing the Right Bedding Type to Reduce Environmental Mastitis

Bacterial exposure at the teat end is a primary source of exposure to potential mastitis pathogens. Reducing this exposure is an important aspect of controlling environmental mastitis. It is especially important reduce exposure to Gram negative bacteria (such as coliforms) because these bacteria often result in increased clinical cases of mastitis even if the SCC of the herd is low. Since teats become contaminated with environmental bacteria through contact, choosing the right type of bedding for your herd is critical. Teats may be in direct contact with bedding materials for 12 to 14 hours per day, making bedding a primary reservoir for environmental pathogens.

When a cow lies down, her udder and teats come into contact with whatever she is lying on. The type of bedding and how that bedding is kept clean are critical issues for control. The ideal bedding for limiting environmental mastitis is a clean inorganic material. If kept clean, sand allows urine to drain down away from the cow, and is less likely to have bacteria growing in it than an organic bedding. However, sand can be expensive and it is more difficult to eliminate the feces-spoiled waste, compared with organic forms.

The primary forms of organic beddings used today are sawdust and straw. In addition to straw, other types of plant materials from wastage of crop harvesting have been used and some are still used (such as corn cobs). Organic beddings soak up fluids from urine, but also are good media for bacterial growth. Feces-spoiled sawdust or straw can be a major source of environmental pathogens for causing mastitis. In addition, green sawdust from uncured wood can harbor some types of Klebsiella bacteria, even before it becomes soiled with feces.

Large amounts of bedding have also been obtained from mechanical liquid-solid separation of manure on some farms in the West. Yet the Midwestern climate is not as arid and the risk of increased mastitis increases in bedding that contains more moisture. Research data on the use of manure solids as bedding material for dairy cows, milk quality on farms using solids, the chemical and bacteriological characteristics of solids, and methods of obtaining solids for bedding in the Midwest are still underway. Though, it appears that excellent cow preparation at milking time, sanitation of milking equipment, cow hygiene, adequate dry cow housing, very low bedding moisture, and bedding/stall management are critical in maintaining excellent udder health when using recycled manure solids for bedding and making it work. These practices are important when using any type of bedding and even more so with recycled manure solids.

Research: Bedding Types and Milk Quality

Research at the University of Wisconsin indicated that large Wisconsin dairy farms that used inorganic bedding had greater productivity and better milk quality compared with herds using other bedding types.

Fresh and recycled sand and forestry byproducts (such as sawdust and wood shavings) are the most common types of bedding materials used on large Wisconsin dairy farms, but a small number of the largest herds use recycled manure products. As compared with organic bedding materials, use of sand bedding has been associated with reduced exposure to bacteria. Recycling bedding on-farm may provide economic opportunities for dairy producers. However, some recycled bedding materials (such as manure and recycled sand) harbor greater number of bacteria. The greater numbers of bacteria have been associated with increased numbers of bacteria on teats of cows exposed to these materials


The Milking Machine and Mastitis

The milking machine can transmit infection onto teats and influence normal teat health. Milking-time tests allow consultants to quantify the degree to which the milking machine might be contributing to the risk of new intra-mammary infection. Teat size has changed as have increased milk flow rates. Unit attachment has changed increased Milk flow let down has been shown to be associated with the possibility of new intra-mammary infection. Vacuum traces collected during milking can illustrate problems with milk flow or over milking and pressure records can help assess liner movement and compression.

Key Performance Indicator: Milking Systems & Performance

Some key performance indicators for milking systems and milking performance

Milking Machine
Average claw vacuum
35-42 kPa
Maximum claw vacuum fluctuation
10 kPa
Average milk flow
2.3 – 4.1 kgs/min
Use of manual mode of milking (when automatic detachers are used)

5% of milkings
“D” phase of the pulsation cycle
At least 150-200 ms preferably 250 ms
Milking Prep
Premilking teat dip contact time
30 seconds before dry wipe
Prep-lag time (time from stimulation to milking unit attachment)
60 to 120 seconds
Milking unit attachment time
3 to 8 minutes (depending on milk production) not to exceed 8 mins
teats with at least 75% coverage with post-milking teat dip ,Cover the whole teat.


Adjustable Speed Vacuum Pump Controller


VSD controllers can meet or exceed the vacuum stability of conventional regulators if they are installed and adjusted optimally. However, installation and adjustment of VSD systems does require greater skill on the part of the installer than conventional regulation systems. "you have been Warned " The reduction in noise levels achieved by VSD control systems is substantial. Noise reduction is achieved by reducing the noise generated by the vacuum pump (by running at lower speed) as well as eliminating the considerable noise generated by the air admission of conventional regulators. This noise reduction makes for a much better work environment for both cows and humans. The energy saved by using VSD controllers is considerable, averaging 56%, with up to 87% savings observed on some systems. VSD controllers also reduce the starting current of large electric motors, which may be a significant advantage when operated on some power distribution systems.


Good mastitis control begins with worker's that are trained to identify and treat the disease.

Staff training has become a vital piece of the mastitis management . Training your staff is the most cost effective way of reducing mastitis when you include up-to-date information, and practice lessons to evaluate the problem of mastitis

Basic udder anatomy and function
The cost of mastitis
Types of mastitis infection
Sources of mastitis infection
Cow cleanliness and environmental mastitis
Mastitis prevention
Mastitis incidence and actions
Mastitis treatment.

When it comes to managing milk quality and somatic cell count (SCC), every part of the operation, not just the milking parlour should be assessed.
All areas that influence milk quality: the cow, the machine, and the staff.
Environmental factors of milk quality. Training people, stockman ship is key. The way cows are brought to the collecting yard and are treated play a definitive role in how they perform in the milking parlour.

Staff should be taught to walk the cows up slowly, and while in the cubicles, focus on gentle movements instead of pushing cows.

Cows are habitual we should train them to walk in the parlour on their own.

If a cow ever walks through an alley with manure, she is at a higher risk for mastitis we have to remember that in the cubicle, the cow lies on that foot that walked through the manure.”

Part of milk quality is providing adequate feed and clean water at all times. Anything that stresses the cow impacts milk quality.

All part of Good Staff Training.



Liner Slip

Liner slip occurs when the liner loses contact with the teat skin and permits entry of air into the milking system. This causes a sudden drop in vacuum pressure, facilitating reverse flow and impacts and increasing the risk of mastitis. Liner slips occur with greater frequency near the end of milking. Slipping in late milking is commonly caused by poor cluster alignment, uneven weight distribution in the cluster or poor liner condition. Liner slipping early in milking often results from a low vacuum level, blocked air vents or restrictions in the short milk tube that lead to overloaded clusters. The percentage of slips may be enhanced if the teats are not dried properly before milking



Dynamic Milking Machine Test

Most of the available scientific literature concerning claw vacuum drops and fluctuations (identical to teat-end vacuum) during machine milking has been published in the 1960s and 1970s. Fewer studies have been carried out more recently on modern types of dairy cows, and milking machines, and have been evaluated with modern statistical methods and software. Based on the accessible information, there are indications that reduced milking performance, leading to long machine-on time mainly as a consequence of a combination of vacuum drops and different types of fluctuations, may influence udder health in a negative way although scientific proofs are scarce. Based on an ISO note, the claw vacuum should remain within a range of 32–42 kPa during peak milk flow to ensure fast, complete and gentle milking. This range of vacuum pressure allows adequate liner movement and a sufficient pressure on the teat during the massage (d-) phase is guaranteed. Thus, liner slips caused by too low claw vacuum are avoided. On the other hand, the teat-end vacuum should not be much higher than 42 kPa as it can cause damage of teat tissue mainly during periods of low milk flow when it is almost identical with the system vacuum. Depending on the used system of milk transport through the tubes, the teat-end vacuum drops to some extent, intensified during periods of high milk flow and reduced during periods of low or absent milk flow at the start and end of milking. Hence, a general increase of system vacuum throughout milking is not suitable, as high teat-end vacuum acting on the teat during milking phases with low milk flow rates have to be avoided. However, a reduction of machine-on time and high vacuum load on the teat during low milk flow can potentially be achieved by early cluster removal, before complete cessation of milk flow. Ideally, this goal can be reached at quarter milking (as used in automatic milking systems) where each teatcup is individually removed based on the milk flow of the individual teat, and milking at very low or no milk flow can easily be avoided.

What is Liner Compression?

Liner compression is the mean compressive pressure (expressed in kPa above atmospheric pressure) applied to the inner tissues of the teat apex by the liner during the d-phase of pulsation. One component ofliner compression has been defined as Over-Pressure by Mein et al. (2003) as the mean compressive pressure, above that required to just start or stop milk flow from the teat, which is applied to the inner tissues of the teat apex by the liner during the d-phase.


How Vacuum Level and Regulator Position is critical.

Differences in vacuum levels between the receiver and regulator should not exceed 0.6kpa. The most common cause of ineffective vacuum regulation is an excessive vacuum difference between the receiver and regulator because of either improper regulator location or excessive restrictions in pipelines and fittings between these two components. Regulators mounted on branch lines often perform inefficiently unless the connecting lines are adequately sized to minimize frictional losses. Branch lines are fine as long as they are sized according to the guidelines. Regulators mounted on or near the distribution tank often tend to oscillate because of the cyclic vacuum changes in pulsator airlines. Preferably, the regulator (or its sensor) should be connected near the sanitary trap so that it can sense, and quickly respond to, vacuum changes caused by "unplanned" air admission entering the system through the teatcups.

• Proper bedding management for all production groups is critical for the effective control of mastitis and promotion of cow comfort.
• High moisture levels of organic bedding materials will result in rapid growth of environmental bacteria in the bedding contribute to high populations of bacteria on teat ends. Bacterial populations in organic bedding materials of small particle size will increase rapidly when contaminated and increase teat end exposure to pathogens.
• Inorganic materials such as sand do not support the growth of environmental pathogens and usually result in lower teat end bacterial counts and subsequently a lower new infection rate


Many consider sand to be the gold standard of bedding materials. It is inert and does not support the growth of bacteria. Sand should be of builders’ quality and contain little or no silt or clay. When properly maintained sand provides a very comfortable medium for bedding. Sand particles tend to move rather than compact, forming a more comfortable resting surface that conforms to the cow’s body. Bacteria counts of used sand bedding are often significantly lower than in organic bedding materials. Lower bacteria counts are associated with reduced rates of new infections with environmental pathogens. A big disadvantage to using sand is that it settles at the bottom of lagoons and manure collection pits and can cause excessive wear on manure spreaders, pumps, and separators.

Teat Condition

Short-term changes in teat condition are generally regarded as those seen in response to a single milking. Faults in milking machines or milking management are the primary cause of short-term effects such as changes in colour, firmness, thickness, or swelling of teats. Colour changes Some teats are noticeably red, either at the teat-end or over the entire teat, when the cluster is removed. Others may become reddened 30-60 seconds after cluster removal. In extreme cases, teats may be blue or become blue when the unit is removed. Swelling or ringing at or near the teat base When examined after milking, the upper part of the teat (teat base) may have a visible line or mark due to contact with the liner mouthpiece lip, or visible swelling (with a palpable, thickened ring) around the upper part of the teat barrel that had been positioned within the mouthpiece chamber of the liner. Swelling or firmness at or near the teat-end Normal teats should feel supple and soft after milking and may contract when touched. Negatively affected teats may be swollen or firm, or in extreme cases, hard and unresponsive to touch. Teats may look flat or “wedge-shaped” after milking.

Teat Condition Causes

Short-term changes in teat condition may be caused by factors such as over-milking, liner type and shape, cluster weight, high milking vacuum, high mouthpiece vacuum, faulty pulsation, pulsation failure, and teat cup crawling. Monitoring teat condition on a regular basis can be a useful tool for determining effectiveness of milking equipment, assessing changes in equipment settings or milking staff, and for early detection of problems.

There are in fact around 140 known causes of mastitis, but the three most common ones are Streptococcal, Staphylococcal and Coliform bacteria.

By identifying the cause of the occurrence, both the treatment of the clinical symptoms and the underlying factors causing the disease can be tackled more specifically. Good, effective therapy will reduce the financial losses from mastitis, benefit dairy cow welfare and improve milk quality and sa


Teat damage refers to teat sores or teat end damage, and it is a major cause of mastitis. It is usually caused by faulty milking machinery, over-milking, exposure to water, or injuries

Teat sores Exposure water and/or faulty machinery
Blueing of teat ends Defective pulsation, excessive vacuum, or incompatible liner/shell combinations
Horizontal rings Defective pulsation, excessive vacuum, or incompatible liner/shell combinations
Swelling of teat end Defective pulsation, excessive vacuum, or incompatible liner/shell combinations
Pulled out teat end Persistent high vacuum, faulty pulsation and/or persistent over-milking
Teat orifice damage (hpterkeratosis) Persistent high vacuum, faulty pulsation and/or persistent over-milking. May be aggravated by insufficient emollient in teat spray
Pin point bleeding Poor machine function and suboptimal pulsation
Black scabs (black spot) Faulty milking machinery causing the teat orifice to prolapse and become ulcerated
Cracked teats Lack of emollient in teat spray

Ensure milking machinery is completely checked at least once every 6 months.

  • Milking Machine Testing

    THE MILKING machine is often blamed as a major cause of mastitis and milk quality problems. To minimise problems it is vital to test the plant while cows are being milked We find equipment problems on most dairies even though 90% or more of the farms that we visit are maintainedFind out more

  • Mastitis Control

    Mastitis is costing the UK dairy industry around £150 million a year and is the third most common reason for cows to be culled.Find out more

  • Advisory Service

    If a client is not achieving premium payments for his or her milk we can investigate the reasons for this and help them to produce milk of a quality that will attract these payments. Such an investigation might involve analysing the incidence of mastitis in the herd, the tube usage, the individual somatic cell counts of the cows and reviewing the milking routine and the environment in which the cows liveFind out more